Can slow cooling of steel after forging replace normalizing?
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May I ask what kind of steel can be slowly cooled after forging instead of normalizing?
General structural steel has requirements for grain size (usually ≥ grade 5). As long as you control the final forging temperature well, the grain size after forging is above grade 5. If the use requirements of the workpiece are not high, air cooling after forging instead of normalizing is completely acceptable. However, air cooling after forging will retain the defective structure formed by high-temperature forging heating, and it is easy to obtain a network or band-like structure. At the same time, the effect of refining the crystal material is not good. At the current level of domestic forging, it is better not to replace it.
Can't. The process of normalizing heat treatment is: “A heat treatment process in which steel is heated to a temperature above complete phase transformation, kept warm for a certain period of time, and then cooled in the air. ” First, is the final forging temperature appropriate? ； The second and main link is that without the heat preservation time, the purpose of normalizing cannot be achieved.
Slow cooling after forging cannot replace normalizing. Please pay attention to what normal fire is